HCY 522
14 Aug 2005 · System & Design MalfunctionHELIOS AIRWAYS FLIGHT 522
Boeing 737-300 · Helios Airways · Image: Wikimedia Commons
Why it happened
Pressurization left in manual; crew hypoxia
Cabin pressurization selector
Hypoxia
Warning horn misinterpretation
Aircraft
Boeing 737-300
Helios Airways
Route
Larnaca (LCA), Cyprus
→ Prague (PRG), Czechia
People
121 on board
121 fatalities
Date
14 Aug 2005
Flight crew
Captain: Hans-Jürgen Merten
Category
System & Design Malfunction
When software, sensors and design turn on the crew.
THE STORY
A pressurization switch left in MANUAL starved everyone of oxygen. The 'ghost flight' circled Athens on autopilot until the fuel ran out.